[Ill.u.s.tration: FIG. 7.]
[Ill.u.s.tration: FIG. 8. Tent-caterpillar.]
They live in this way four or five weeks, becoming, when full grown, about two inches long and nearly as large as a lead-pencil. See fig. 8.
They are black, with light-colored tufts of hair on the back. Down the center of the back is a white line bordered with irregular yellowish lines. The sides of the body are marked with pale blue, while the under side of the worm is black. When grown they pa.s.s to the ground and hunt a sheltered place, where they spin a coc.o.o.n, from which, in about three weeks, emerges the adult moth, fig. 6, the color of which varies from yellowish to reddish brown. The front wings each contain two oblique, whitish lines, dividing the wing into three nearly equal parts. These moths are night flyers during the last half of June and first half of July. They eat nothing. The female lays her eggs as described, and dies.
_Remedies._ Spare the birds; put up boxes for the bats and owls. Cut off the egg cl.u.s.ters during the winter. Cut and burn the tents, or burn the tents on the tree, with any kind of a torch. Early morning or late evening is the time, as they are then all home. Spray the foliage nearest the tents with solutions for canker-worm.
CODLING-MOTH.
The apple-worm, which every apple eater has found many times in the apple, is the child of the codling-moth. See _b_, fig. 9. It is a scourge all over the apple-growing district. It destroys or reduces the value of the apple crop many millions of dollars annually.
[Ill.u.s.tration: FIG. 9. _a_, Female Codling-moth. _b_, Larva of same in apple.]
The parent--adult insect, or moth--see _a_, fig. 9, is a small moth with a spread of wings three-fourths of an inch, the first pair marked with wavy lines of gray and brown, with a large, oval brown spot, streaked coppery, on hinder margin. The hind wings are yellowish brown. These moths appear, and begin to lay on the surface of the leaves, in the calyx, or on the surface of the apple, about the 1st of May. The eggs hatch in about one week, and the young worm immediately begins to burrow into the apple, working its way to the center, where it works around the core, gaining strength and size for about three weeks, when it leaves the apple and seeks a hiding place in which to spin its coc.o.o.n, the favorite place being under projections of the rough bark of the tree.
When first hatched these worms are small, hardly one-eighth of an inch long, white, with a black head and shoulders. When mature, the body is pinkish and the head and shoulders brown. The adult, _a_, fig. 9, issues from the coc.o.o.n in about two weeks, appearing near June 15. They commence at once to lay eggs. The worms of this, the second brood, live in the apple all winter, and it is these that disgust the apple eater and cut the profits of the orchardist.
_Remedies._ The same spray as for canker-worms, used just after the petals of the blossom fall. No eggs are deposited earlier than this. At this time the calyx cup is open, and a little poison in it is apt to prove fatal to the infant worm. In a few days after the egg is laid the calyx closes, and no spray will reach the worm. Remember, this early spraying does away with the parents of the _second_ brood, and hence should not be neglected. Bands of burlaps, paper or other material, loosely tied about the tree before June 1, make attractive places for the worms to pupate in. These bands should be examined often, say weekly, and all worms killed. Fallen fruit should be gathered and fed to stock. Cellars, caves and fruit houses should be thoroughly cleaned and fumigated and the cleanings burned every spring, as many thousands of moths are wintered over in them.
FLAT-HEADED BORER.
The adult, fig. 10, is flat, about three-eighths of an inch long, of a greenish black with coppery reflections. They appear about the last of May and deposit eggs from then until September. They generally lay their eggs in a diseased portion of the tree, where it has been bruised, or sun-scalded, or in trees of weak vitality, in bad health from lack of cultivation or moisture, or from soil poverty. The eggs are small and yellowish, and are found singly or in numbers in crevices in the bark.
The larva, or borer, fig. 11, when young, is yellowish, with a broad, flat head; it soon bores to the sap-wood, where it feeds. At this time it is easily discovered by the "castings" from the opening. As they become older and larger they bore into the harder wood, making flattened chambers. In about a year they gnaw a channel to the outside, excepting a thin layer of bark, and backing a little way they crowd castings to the front and change into the perfect insect, emerging about the last of May.
[Ill.u.s.tration: FIG. 10. Adult Flat-headed Borer.]
[Ill.u.s.tration: FIG. 11. Larva of a Flat-headed Borer.]
_Remedies._ Keep the tree thrifty, free from bruises or sun-scald, and the flow of sap will drown them. If any are detected by the castings, cut in, and use a hooked wire to pull them out. Some washes will deter the female from depositing eggs. For instance: Equal parts of soft soap and sal soda, with enough crude carbolic acid to give a strong odor.
Apply with a brush several times in a season, especially where the bark appears unhealthy.
ROUND-HEADED BORER.
Attacks the same trees under the same conditions as the flat-headed borer. The adult, fig. 12, is about five-eighths of an inch long, brown above, with two white stripes the whole length of the back. Head and under surface grayish. It is a night flyer. The female appears about June 1, and stays until September. She deposits her eggs at night, in small incisions made angling into the bark, generally near the ground.
In about two weeks they hatch, and the little borers, _a_, fig. 13, begin to bore their way into the inner bark and sap-wood, leaving the bore filled with "castings," fig. 14. For two summers they stay in the sap-wood and do great damage, often girdling young trees. After the second winter they cut channels up into the hard wood; attaining their growth by fall, they burrow outward to the under side of the bark, and there remain until spring, changing to adults. See _b_, fig. 13. They then gnaw through the bark, and emerge about June 1 to propagate their species.
_Remedies._ Same as for flat-headed borer.
[Ill.u.s.tration: FIG. 12. Adult Round-headed Borer, greatly enlarged.]
[Ill.u.s.tration: FIG. 13. Larva and pupa of the Round-headed Borer.]
[Ill.u.s.tration: FIG. 14. _a_, Incision in which egg is deposited; _b_, same, the wood has been split along line _a_; _e_, showing egg in place; _c_, showing how egg is inserted under bark; _d_, egg greatly magnified; _e_, hole through which adult emerged; _f_, channel of larva; _g_, insect in pupal state just before issuing as an adult.]
TREE WASHES FOR BORERS.
Observations by members of the Kansas State Horticultural Society.
A. Chandler: I used a tree wash last year on apple trees for borers and insects. I have been troubled in my timber (recently cleared) land with borers, and if I had not taken this precaution they would have been worse. It is known as the "Carnahan tree wash." Obtaining it ready prepared in a can, I applied it in June with a whitewash brush to the tree trunks and a portion of the limbs, and found it very beneficial.
While it will not _destroy_ the borer, I think it will prevent the borer beetle from depositing eggs on the outside. From the healthy appearance of the tree and the smooth appearance of the bark, I think it equals anything I ever tried. It is also good for the prevention of other insects, as tree-crickets, etc., and I think it will destroy the curculio to some extent, and will prevent insects climbing the trees. My trees never looked more thrifty. I cannot say it will prevent root-rot.
F. Holsinger: I would like to inquire whether your ground was thoroughly cultivated?
A. Chandler: All the cultivation I could give would not prevent borers.
I applied the wash from the ground up, as far as I could reach. It costs about two cents per tree from four to six years old, and I do not know but what that might be reduced. This wash is obtained in gallon and half-gallon cans. It should be applied about twice a year--spring and fall--costing about four cents per year for each tree.
T. A. Stanley: Would not a strong lime wash do as well.
A. Chandler: No; I have no success with it. If the borer is in the tree, you must dig him out with a knife. By examination you can tell whether borers have deposited eggs or not. I do not say it will rid the tree of borers if they have been allowed to deposit eggs and are left for years.
It makes the tree grow more vigorous. I do not know what is in this tree wash, but it did no damage.
B. F. Smith: Chandler has tried this wash, and it has proven successful with him. There are always new things being tried. If he has found something good for trees, we should not object to it. If I receive a package I will try it.
T. A. Stanley: My experience with borers will date back as far as fifty years ago, when I was a boy, and the best thing to exterminate them with was a jack-knife. A Boston gentleman visiting my father went into the orchard and asked father if he had ever seen any borers. Father told him he knew nothing about them (they were something new in those days).
Examining a tree, he took out his jack-knife and went to work near the ground, and he soon showed why the tree was not doing well. With his knife he dug the borer out and said the jack-knife was the best exterminator he knew of. My experience is, if you will attend to it about the 1st of June, when the beetles come out on the tree and deposit their eggs behind loose scales of bark, and wash the tree with strong lime wash, it will kill them. I prefer lime wash to any "nostrum" ever introduced. When they once get into the tree no wash will take them out.
Horticulturists have been deceived enough by patent nostrums.
E. J. Holman: By instinct this insect never lays its eggs on the surface. It lays as completely in the wood as the locust, which punctures almost to the heart of a twig. A borer lives three years in the wood; the third year it comes out in perfect form. It goes below in the wood every winter, and the third spring pa.s.ses the coc.o.o.n stage there. They lay about fifty eggs, each placed separate and apart in the wood. Rarely does an egg fail to hatch.
J. W. Robison: These beetles are very fierce. Put a half dozen into a bottle and they will beat a bull fight, and will not stop until they kill each other. She is a philosopher; she makes punctures sideways, so the eggs can be laid in a row, and the bark close over them. It is only a few days until they hatch; open the lip where deposited and you can see them plainly. Without cutting the bark, thrust your knife under the lip and you can hear the eggs crack. The larva works round and round until of the size of a pea, and then usually starts upward until he gets level with the surface of the ground, staying there until the next season. He comes up early in the spring. My practice is to hoe around the tree before the time for the round-headed borer to deposit eggs. I keep the weeds clear, so that I can see where the borer went in. If he has been in a year or two he is near the middle, and you had better let him alone, as it will injure the tree to remove him. It is impossible to get rid of these borers by a wash, because the eggs are covered. There is no connection between the round-headed and flat-headed borers.
T. A. Stanley: It requires three years for the borer to mature and come out. In my experience, the borer selects a spot where loose bark is on the tree, and goes in where it is tender. It lays eggs in even rows.
These eggs stay under the bark but a short time when they hatch and the little worm eats into the tender bark, and goes through it, to live and grow there; when large enough they go into the body of the tree. They stay there for three years. Sc.r.a.pe off the bark and put whitewash on the eggs and it will destroy them.
President Wellhouse: By taking a knife, cutting into the tree, and running a hooked wire in, you can pull them out. Each female beetle deposits fifty or sixty eggs, and we find it better and less expensive to hunt the borers early in the spring. By carefully examining the bottom of the tree for six or eight inches above the ground you will see a little brown spot. He came to the bark the fall previous, and sets about two inches back in his cavity. If you wait till May, he is out and gone; he is easier taken out in spring than later. By killing the insect you prevent the egg laying. We always have our men hunt for the insects that are about to come out. It is easy to find the little brown spot about the size of your finger end, and you can kill them by pouring a few drops of coal-oil from a machine can into the cavity.
Dr. J. Stayman: Can we prevent the borer from entering the tree? I have practiced banking up my trees as steep as I can, about a foot high; less may do. The beetle will not deposit eggs where the tree is banked up. I have practiced this for thirty years, and have never seen a borer in my trees since I began it. Like these gentlemen, I at first cut out the borers. We can prevent them by banking up early in the spring. By instinct, it knows the bank will wash down. If it deposits its eggs, how easy to sc.r.a.pe away the mound. I never saw a flathead borer on a tree that was banked. They always work on the south side, where the sun shines on the tree.
BUD MOTH.
This insect is often very destructive, attacking the blossom and leaf-buds, and in a few mouthfuls destroying that which must make the leaves and fruit, "nipping in the bud" the entire crop of fruit and debilitating the tree. This worm works in early spring, as soon as the buds begin to open; it delights in the prominent terminal buds and its work stops all new growth, causes many leaves to turn brown, and thus brings to the notice of the orchardist its bad work. The moth measures about three-quarters of an inch across its wings, and is mainly a gray color, the middle of the fore wings being lighter, or creamy. This insect first appears on the buds as a small, dark brown worm, about one-fourth of an inch long, with shining black head and shoulders. It imbeds itself in the center of the bud, tying the leaves together with its web. It is an irregular worker, and leaves the bud in a ragged, brown, dilapidated condition.
Its work is most destructive in the nursery, destroying terminal shoots, which sadly interferes with the growth and symmetry of the young tree.
Sometimes it burrows from the bud into the pith of the twig for several inches, killing the shoot to the tip. The worm finally settles upon a leaf, cutting the leaf stalk partly off, so that the leaf withers; it then rolls this soft, wilted leaf into a tube around its body, fastening it with webs and lining it for a nest. From this tube nest it comes forth only at night to feed, and when disturbed it hastens into it out of sight. In feeding, it draws leaves towards its home by silken threads, thus forming a bunch of partly eaten leaves, which turn brown, making the nest conspicuous.
After attaining its growth it lies as a pupa in its silk-lined tube about ten days, when it emerges an adult moth, and in three or four days begins to lay its eggs. These moths appear from about June 1 and remain to July 5 or July 10. They are night flyers, and do no damage in the winged state. As the worms are leaf-eaters, spraying with London purple or Paris green, as for canker-worms, must kill many. Whenever their nests are seen they should, if possible, be gathered and burned, and in a badly infested orchard it will pay to rake and burn all the leaves under the trees.
APPLE CURCULIO.
[Ill.u.s.tration: FIG. 15. _a_, Beetle, natural size; _b_, beetle, magnified; _c_, side and back view of same, magnified.]
[Ill.u.s.tration: FIG. 16. _a_, Pupa stage; _b_, larva, or worm. Hair-lines to the left of pupa show natural size.]